The invention relates to an injection molding machine with a machine frame, a stationary and a movable die platen as well as a front plate supporting a closure mechanism wherein the front plate on which is supported the movable die platen via the closure mechanism and the stationary die platen are connected without bars, exclusively via the machine frame so that the closing force occurring during the closing process and the lifting force occurring during injection between the front plate and the die platen are borne only by the machine frame wherein the movable die platen is guided on at least one rail supported on the machine frame.
An injection molding machine of this type is known from European Patent Document EU-0 311 133-B1. Since an injection molding machine of this type does not comprise any bars, the closing forces can only be borne by the machine frame.
An injection molding machine of this type offers better access to the injection molding die so that retooling time can be considerably reduced. Difficulties arise, however, in that the closing forces which occur cannot be borne centrally. According to the cited patent document the problem was solved in such a way that between the hydraulic piston which moves the movable die platen and the die platen itself, an articulation is provided which allows the die platen to tilt about a horizontal axis. It is thereby ensured that during the injection molding process the two die platens are always parallel to each other.
The use of an articulation mechanism, however means greater constructional expenditures.